Image via ljubaphoto/E+ via Getty Images This article is republished here with permission from The Conversation. This content is shared here because the topic may interest Snopes readers; it does not, however, represent the work of Snopes fact-checkers or editors. Frequent and long-term use of lye-based hair straightening products, or relaxers, may increase the risk of breast cancer among Black women, compared with more moderate use. Boston University’s Black Women’s Health Study followed 59,000 self-identified African American women for over 25 years, sending questionnaires every two years on new diagnoses and factors that might influence their health. The minimal association between hair relaxers (with or without lye) and breast cancer risk for moderate users is generally reassuring. But the elevated risk for the heaviest users of lye-based hair products – which included about 20% of study participants – is concerning.